The conventional seat cushions are configured into sheets of different shapes having different seat heights filled with sponge, foam, synthetic fiber, or other solid materials. When different weights are applied on the seat cushion, it will be leveled equally across the sheet.
In the seat cushion according to the present invention, when body weight is transferred back and forth, the amount of fluid or gas contained therein which defines thickness of the seat cushion will be transferred back and forth which results in a continuous movement of muscles connected to the hip, coccyx and lower intervertebral discs for highest benefit of the user.